[Livechat] Non available Livechat forwarded to different Department

Description:

We've created several Departments for the Livechat. Let's call them X, Y and Z. For each of these Departments we set Show on registration page to no.

Afterwards, we created three embedded seperate Livechats Windows using the Function:

<script type="text/javascript">
(function(w, d, s, u) {
    w.RocketChat = function(c) { w.RocketChat._.push(c) }; w.RocketChat._ = []; w.RocketChat.url = u;
    var h = d.getElementsByTagName(s)[0], j = d.createElement(s);
    j.async = true; j.src = 'http://ROCKETCHAT-URL/packages/rocketchat_livechat/assets/rocketchat-livechat.min.js?_=201702160944';
    h.parentNode.insertBefore(j, h);
})(window, document, 'script', 'http://ROCKETCHAT-URL/livechat');
RocketChat(function() {
    this.setDepartment('DEPARTMENT');
});
</script>

and set under Appearance "Livechat offline--> Display Offline Form: False" which is working fine.

The problem is that as soon as Department X is Offline and Y goes Online, the Chat Window is shown again and therefore the Chats are forwarded, which is not the desired outcome.

Steps to reproduce:

Open Livechat Page for Department X when X isn't Online Livechat Window Appears User fills in their Data Livechat will be forwarded to Department Y

Expected behavior:

Show no Livechat Window when the actual Department is Offline and another one is Online.

Actual behavior:

Livechat Window for Department X comes up when Y or Z are Online

Server Setup Information:

Version of Rocket.Chat Server: 0.74.0
Operating System: Ubuntu 16.04 LTS
Deployment Method: tar
Number of Running Instances: 1
DB Replicaset Oplog: Disabled
NodeJS Version: 8.11.3
MongoDB Version: 3.4.19

RocketChat / Rocket.Chat.Livechat